The surreptitious observation of microprocessor function(s) has become a concern to many designers. For example, the surreptitious observation of microprocessor function(s) by an unauthorized entity can result in such entity being able to illegally appropriate highly confidential and proprietary information. However, to obtain such information requires a large amount of data to understand the functions of the processor. So, even if the unauthorized entity has access to the processor, it is still exceedingly difficult to store the data needed for any length of time in a processor without detecting a new memory array.
As it remains exceedingly difficult to store the data needed for any length of time in a processor without detecting a new memory array, it becomes necessary for the unauthorized entity to spirit away machine information in real time through an existing information path. The venues available to do this include, for example, conventional pins (i.e., JTAG), power or heat signatures, backside photoemissions, or most likely electromagnetic emissions. As to the latter possibility, chip electromagnetic emissions are readily available and can easily be recorded and decoded. While the designer (and others) considers this electromagnetic interference (EMI) to be undesirable, this is precisely what can be used to spy on machine functions and, once decoded, obtain the highly confidential and proprietary information. To do this, an unauthorized entity can readily pick up these RF signals and use them to help deduce what the chip is doing, and what data it is doing it on.
Accordingly, there exists a need in the art to overcome the deficiencies and limitations described hereinabove.